Edward A. Chapin.
Early States of Staphylinidæ.
Psyche 22:157-160, 1915.

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19151 Chapin-Earl9 States of Stuphylinidm 157 ment with a length five times its diameter and apically a spindle-shaped, fingerlike process, Palpi; the first segment irregularly ovate, the second with a length five times its diameter, the thiid as long as the second, the fourth one-fourth longer than the thiid.
Eyes holoptic.
Mesonotum reddish brown, the submedian lines yellowish, ScuteIlum and postscuteUum yellowish brown, Abdomen rather thickly haiied, mostly dark brown, the incisures dorsally lighter, the venter darker, the ovipositor pale yellowish. Wings strongly marked with dark brown and white patches as follows; on the basal thiid of the third vein an irregularly, quadrangular, whitish area slightly restricted disially on the third vein and divided by it; at the distal fourth, between the third vein and costa, there are two irregular, transverse, whitish bands, the outer one nearly broken and almost forming a V; caudad of the third vein, near its distal fourth and nearly opposite the irregular, transverse bands mentioned above, are two irregular, angulate, whitish spots close to the third vein; along the fifth vein, near the middle and at its distal fourth, are two ill-defined whitish, angulate areas extending on both sides of the vein; in the anal area there is a lunate, whitish area extending from the fifth vein along ib branch to the pos- terior margin, and basally thereof, a pyriform, whitish area; halteres whitish trans- parent. Cox= reddish brown, femora dark straw; tibk and tarsi mostly pale straw, the distal tarsal segments darker; clam moderately stout, strongly curved, simple, the pulvilli rudimentary.
Ovipositor short, the terminal lobes sparsely setme and narrowly oval.
Type: Cecid. 1597.
EARLY STATES OF' STA4PHYLINIDB.
I, XANTHOLZNUS CEPHALUS SAY.
BY EDWARD A. CHAPIN,
New Haven, Connecticut.
On July 24,1914, while collecting larve under the bark of decay- ing Pinus rigida Mill., at Springfield, Mass., a number of Staphy- linid larvze, of apparently the same species, were taken. These Iarv~ were reared and the beetles identified as Xuntholinus cephah.~ Say, Since that time I have taken the same species under the bark of Custunea dentata (Marsh) Borkh., showing that the species is not confined to Pinus. Hamilton (Canadian Ent., 1891, Vol. 23, p. 60) notes the species as occurring under bark at Allegheny, Pa., and also under rubbish on the coast at Atlantic City, N. J. The rearing was done in plaster-of-Paris nests, modified slightly from those designed and used by Janet ('93) for rearing ants, and similar to those used by Dimmock ('04) in his work on the Cara- bid*. Very little difficulty was experienced, the lame feeding



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158 Psyche [October
readily on small maggots, such as are found under decaying bark. Two lam= were preserved in alcohol, as were a few pup=. The rest were allowed to pupate and emerge. All larval and pupal exuvi~ were preserved. It is from this material that I have made the observations recorded in this paper. -
At this time, I wish to extend my sincere thanks to Dr. George Dimmock of Springfield for valuable aid and suggestions, to the staff of the Osborn Zoological Laboratory, Yale University, for the use of laboratory instruments and facilities, and to Mr. Herbert S. Barber of the National Museum, for identification of the species. Larva of Xantholinus cephalus
Form depressed slender fu~iform~ with ventral side of body straight? fitted for locomotion on flat surfaces, eight and one-half times longer than wide? head and thoracic segments nearly equal in width? greatest width at fourth abdominal seg- ment. Length of mature larva? 9.5 mm. Head quadrate? depressed? sides nearly parallel.
Neck five-eighths width of heady with a V shaped indentation on ventral posterior margin, Epistoma pentagonal? reaching posteriorly about one-third dis- tance from anterior margin of clypeus to posterior margin of head? with V shaped indentation in lateral margins? with a large seta slightly posterior to apex of inden- tation. Other set= symmetrically arranged. Frontal angles not prominent. Clypeus not separate from epi~toma~ dentate on anterior margin? one tooth at middle and four teeth on either side? the first tooth from the middle being the largest. Numerous large set= symmetrically arranged. Hypostoma somewhat pentagonal, about one-half length of head.
Four set= arranged along lateral margins. Horn on each anterior angle? directed forward? one seta at base of each horn. Ocelli minute? probably four? confluent.
Not apparent in shed larval skins.
Antenn~ four
jointed? slightly longer than mandibles; first joint nearly hemispherical, nearly as wide as long, no set=. Second joint clavate cylindricaly one-fifth as wide as long and four times as long as the first? with a single seta situated near the base on the external dorsal side. Third joint fusiform four times longer than wide and four- fifths as long as the second? outer ventral angle obliquely truncated and bearing on the truncation a prominent acorn shaped appendi~, five set= situated on the upper half of the third joint. Fourth joint slender? somewhat clavate, bearing three large and four small set= on its tip. Antenna1 formula: -05 91 -1'7 (-03) .lo. Mandibles three times longer than wide? toothlessy slender acuminate falciform, three set= on outer margin, a small one near the base, a large one the same distance in advance? and a third, small? slightly less than half way between base and apex. Maxille equal in length to antenne, Maxillary stipes slightly less than half length of mandible? subcylindrical, five times longer than wide? apex obliquely truncated on inside, with four set= on outside and two on inside along margins. Outer lobe seven-ninths as long as first joint of palp? a single slender, conical joint four times longer than wide? with a single stout seta at apex. Inner lobe lacking. Palpigerous stipes stout? cylindricaly two-thirds as wide as long, unadorned. Maxillary palp



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19151 Chapin-Early State8 of 8taphgZinid~ 159 two-thirds as long as maxillary stipes? first joint twice the length of the palpigerous stipes and nearly equal in-width, with two set=? one on interior margin? one-third of distance from base to apex and the other on the exterior angle of the apex. Second joint two-thirds length of first and two-thirds width? subcylindrical, un- adorned. Third joint one-half length and width of second? cylindricaly slightly acuminate, unadorned. Formula of maxilla: Stipes? -31 Palp, 21 Lohe? -07. Mentum exerted, Stipites of labial palpi concrete? taken together somewhat de- pressed clavate? with a shallow indentation on either side of apexy densely clothed with minute set=. Ligula present, minute, conical. Labial palpi two jointed with terminal appendix. First joint cylindrical, slightly longer than palpigerous stipes, three times longer than wide, unadorned. Second joint cylindricaly slightly fusi- form? same length as first, slightly narrower. Terminal appendix tapering cylin- drical? two-thirds as long as second joint? unadorned. Formula of labial palp: -06 .06 (.04). Thorax composed of three well defined segments. First segment rectangular, nine-tenths as wide as long? tapering posteriorly, slightly chitinous. Numerous set= arranged as follows: seven large? on or near lateral margins (one at middle, four at anterior angle and two midway between middle and posterior angle).
Two on anterior margin? each half way between angle and midline. Two
similarly placed near posterior margin.
Second segment rectangular, equal in
width to first and four-fifths as long. Not chitinous. Numerous set% as follows: Five large, on or near lateral margins? somewhat as in first. One seta near each anterior angle. Other minute set= present. Third segment: same size as second. One large seta on margin near anterior angle. Other minute set=.
Abdomen com-
posed of nine segments? the last bearing a pair of cerci and anal tube. Segments
progress in width to the fourth, then taper to the end. Numerous set= on each segment.
Anal cerci two jointed, arising from dorsal, posterior margin of ninth segment.
First joint cylindricaly five times as long as broad? with six set= ar- ranged as in Plate IIy Figure 2.
Second joint cylindrical, same proportion as first, with two set= at tip. A minute terminal appendix present. Legs. First pair. Femur stout with a few set= on margins, Tibia cylindricaly same length as femur, armed with a row of seven stout spines on posterior margin. Tarsus cylindrical, armed with stout spinesy eight on anterior and seven on posterior margin. Ter- minates in a single claw.
Second and third pairs, similar to first. Comparative
lengths of legs:
- 1st. 2d. 3d.
Femur.. .................... 25 25 27
Tibia ....................... 24 26 28
Tarsus. ..................... 21 20 22
Pupa of Xantholinus cephalus.
Form coarctate? total length three and one-third times greatest width, greatest width one-third length of pupa from anterior end. Length, 4.8 mm.
Colo~ chitin
colored throughout.
Antennce directed posteriorly from insertion and in living pupa, lie concealed under sides of head. Elytra and wings small? wrapped closely
around body so that they are hardly visible from dorsal surface. Stigmata of thorax
concealed, those of abdomen visible from dorsal side? peritremes protruded? slightly



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160 Psyche [October
darker than rest of body. Set@ absent. Dorsal view: Head and anterior margin of prothorax hidden, Knees of first pair of legs visible at sides of prothoraxy near posterior margin. Knees of third pair of legs project at sides of second abdominal segment. Prothorax rounded triangular, joined to mesothorax by a straight line. Mesothorax convexy suture separating it from elytra not definable. Anterior margin straighty posterior margin with a median protrusion extending one-third into the metathorax, Metathorax slightly convexy same width as mesothoraxy anterior margin following line of joint with mesothoraxy posterior margin straight. Formula expressing ratio of lengths of thoracic segments: 37 18 23. Abdomen: First segment slightly longer and wider than metathorax? second segment but half the length of first and of equal width. Segments increase in width to the fifth from whence they taper to the end.
Stigmata near the lateral margins.
Cerci incon-
spicuous.
Ventral view:
Head semicircular in front surrounded in anterior outline by prothorax and7 from vertex to tip of mandiblesy slightly more than one-third total length of pupa. Eyes not conspicuous until coloration previous to emergence sets in, when they are seen to be just above base of mandibles. Tip of antenna reaches slightly beyond eye. Mandibles slightly more than one-fourth of length of head, closed but do not overlap. Labrum extends down as far as tip and covers interior halves of mandibles.
Labrum notched at tip. Maxillary palps extend slightly below mandiblesy the part in view roughly triangular. Labial palps hidden. Legs: First pair. Femora hidden beneath head with exception of tipsy which are visible at the sides of the head where the antenn~ are inserted. Tibie directed posteriorly from this point and reach to the eyes. Tarsi are nearly parallel and reach posteriorly nearly to the tips of the mandibles. Second pair.
Femora of
second pair of legs completely hidden by head. Tibiz partially hidden by tarsi of
first pair, but do appear outside first legs near the eyes. Tarsi parallel and extend
below the mandibles a distance equal to that across the tips of the maxillary palps. Third pair. Femora are visible and extend in nearly a straight line at right angles to the body. Tibiz extend inward and posteriorly and end at the posterior margin of the third abdominal segment. Tarsi are parallel and extend almost to the middle of the fifth segment.
Osborn Zoological Laboratory,
Sheffield Scientific School,
New Haven, Connecticut.
REFERENCES IN TEXT.
Janet, C. ktudes sur les Fourmis. gme note. Appareil pour l'glevage et lyObser- vation des Fourmis et dyautres petits Animaux qui Vivent Cachks et ont Besoin d'une Atmosphhre Humide. Ann. SOC. Ent. France7 1893y vol. 62, p. 467-482y il.
Dimmock, George and I?. Knab. Early Stages of Carabid~. Bull. Springfield
Mus, Nat. Hist., 1, 1904y p. 4.
Hamilton, John. Notes on Coleoptera. No. 7. Canadian Ent.å 18917 vol. 23, p. 60-65.




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